Time-piece dial



(No Model.) A

II. A. LEWIS.

` TIME PIECE DIAL No. 374,605. Patented Dec. 13, 1887,

UNITED STATES PATENT OFFICE.

EDVARD A. LEWIS, OF ST. LOUIS, MISSOURI.

TIME-PIECE DIAL.

SPECIFICATION forming part of Letters Patent No. 374,605. dated December 13, 1887, Application tiled December 15.2.1888. Serial No. 114,346. (No model.)

.To all whom. it may concern:

Beit known that I, EDWARD A. LEWIS, of St. Louis, Missouri, have made a new and useful Improvement in Time-Pieces, of which the A following is a full, clear, and exact description, reference being had to the annexed drawings, maklng part of this specification, in

whichq Figure 1 is a front or face elevation ot' a 1o time-piece having the improvement; Fig. 2, a

2o scale on the line 7 7 of Fig. 5, and Fig. 8 a

3o graduation.

section upon an enlarged scale on the line 8 8 of Fig. 5.

The same letters of reference denotethe same parts.

This inventionv consists, mainly, in providing a timepiece with a graduation so made and so related to the remaining parts of the timepiece that it can be used partly as a twelve-hour and partly as a twenty-four-hour By means of it 4the ordinary hands can be used and in the ordinary way. Up to midday the ordinary twelve-hour graduation appears, and from midday to midnight the twentyfour-hour graduation is used, the numbers of which appear in the places respectively occupied by those of the ordinary twelve-hour graduation. y

Areprescnts what may be'termed the front dial-plate, for it occupies lthe place of the 4o ordinary dial-plate of a clock or watch, and

it is provided with the ordinary minute graduation, a.

B represents the ordinary hour-hand, and C the ordinary minutehand. These hands are made and operated in the ordinary manner. The plate A has-a series of openings, a a a', at the points, respectively, of the plate hitherto occupied by the numbers of the ordinary twelve-hour graduation. Behind the plate A 5o is what may be termed the rear dial-plate,

D. Upon this last-named plate is a graduation, d. This graduation, as shown in Fig. 3, has twenty-four numbers, arranged as follows: At the top, where the number 12 appears in the ordinary twelve-hour graduation, the number 24 appears, then the number l, then the number 13, then the number 2, then the number 14, then the number 3, and so on. The space between the numbers 24 and 13, as well as that between the numbers 13 and 14 and between the numbers 14 and 15, and so on, as well as the space between the numbers 1 and 2, between the numbers 2 and 3, and between the numbers 3 and 4, and so on, is equal tothe space between any of the adjoining numbers of the ordinary twelve-hour graduation. This dial-plate D is adapted to be rotated reciproeatingly, so that the numbers 12, 1, 2, 3, 4, Sto., can appear in the openings a of the plate A, as in Fig. 1, or so that the numbers 24, 13, 14, 15, Sto., can appear in the openings a', as in Fig. 2.

The operation of the invention as thus far described is as follows: At midnight the number 24 appears at the top opening, a', of the plate A. After midnight and at any time during the ensuing hour the plate D is rotated upon its center d', so as to present the numbers l2, 1, 2, 3, 360.-, as in Fig. 1.- The dial D then remains in the last-named position until midday, after which and during the hour ensuing midday the plate D is rotated backward into its original position, in which position the numbers 24, 13, 14, 15, 8vo., will appear, as in Fig. 2. Thus during the rst half of the twenty-four hours the dial of the timepiece presents substantially the appearance ot` the ordinary time-piece; but during the second half of the twenty-four hours it presents the view shown in Fig. 2; and as the new numbers 13, 14, 15, 35o., appear in the same relative places hitherto occupied by the ordinary numbers 1, 2, 3, &c., it becomes much easier for one to become familiarized with the new graduation incident to the adoption to what is known as the twenty-four-hour standard.

Various forms of mechanism may be employed for reciprocating the dial-plate D in the manner described. That which I consider a desirable form is shown in Figs. 4, 5, 6, 7, 8.

E represents a pinion attached to the hourhand spindle F, and rotating once in twelve IOC) hours. It engages with and drives the gear G. This last-named gear has twice as many teeth as the pinion E. It turns upon the spindle g, and has attached to it the cam I.

J and K represent levers turning loosely upon the bearing F. At one end they are each provided with a stud, j k, for the purpose of engaging with the cam I. The other ends of the levers are adapted to be drawn toward each other by means of the springs 7" k', respectively-that is, the springs at one end are fastened to sonic fixed part of the frame of the time-piece, such as the post L, and the other ends of the springs are attached, re-

spectively, to the levers J K. The movement of the cam, as indicated by the arrows, causes the levers to be oseillated in one direction upon the bearing F, and the springs operate, when the levers are released by the cam, to move the levers back again into their original positionsthat is, more particularly described, when after midnight it is desired to shift the dial-plate D, the gearing and cam are adjusted so as to allow the lever K to move from the position shown in the dotted lines in Fig. 6 into the position shown in t-he full lines in that figure. In this movement the lever K encounters the stud d2 upon the dial-plate D, and in consequence causes the dial-plate D to be moved as desired. Meanwhile the other lever J is in the position shownin the full lines in Fig. 6. After midday, when it is desired to shift the dial-plate D back again, the cam I will have been turned around into the position shown in Fig. 5,whereupon the lever J moves from the position shown in the dotted lines in Fig. 5 into the position shown in the full lines in Fig. 5, and in this movement it encounters the stud d3, causing the dialeplate D to be moved in the manner last described. The levers J K oscillate upon the spindle F independently of each other, and, as shown in Fig. 7 ,it is desirable for them to be separated from each other by suitable washers, M.

The dial D,whileintended to be oscillated, as described, upon the bearing F, should, after having been shifted, as described, be kept from beingaccidentallydisplaced. Forthispurpose some suitable means-such as a washer, N, Fig. 7-may be attached to the bearing F, and so as to bear slightly against the dial-plate D. Then, after the dial-plate D has been shifted into either of its positions, the rotation of the cam I causes the lever last used in shifting the dial-plate to be moved backward from the stud dl or d3, as the case may be, and the lever 'remains away from the stud until the dialplate has by means of the other lever been shifted back again.

I claim- The combination ofthe dial-plate D, having thestuds Z2 da, the spindle F, the pinion E, the gear G, the cam I, the levers J K, and the springsj k', substantially as described.

EDWD. A. LEWIS.

Witnesses:

C. D. MOODY, C. E. HUNT. 

